Confounding Spark-Miss Issue

Hello, I have a Ford 9N that that has me perplexed.

A few years back I converted it to 12 volts, added a Pertronix ignition, a remote 12 volt coil, new wires, plugs, cap, rotor and one wire 12 volt alternator. It ran great for a long time and after a while I garaged it to work on other projects. Ill also mention that it blows some blue smoke when transitioning from idle to full throttle. It has smoked like this going back to the 1980s.

Anyway, I took it out today after not running it for a year or so and it ran badly. It seemed like it wasnt firing on all cylinders. I removed each plug wire while it was running and found that cylinders two and four do not fire with the plug wires fully connected to the plug.

However, cylinders two and four fire perfectly with the plug wires barely attached such that the metal terminal end of the wire does not physically attach to the top of the plug itself. Essentially. the wire is arcing inside the rubber wire cap to the metal spark plug terminal.

It runs great this way, but as soon as I push the wire down against the plug terminal, the cylinder starts to miss.

Strangely, cylinder two fires with the plug wire lying next to the spark plug on the cylinder head flashing and arching across to the base of the plug.

Curious if anyone has experienced this and found a solution.

Thanks in advance for any advice.

Spark plugs are cheap. Buy four, gap them properly, and install them. See if
the problem goes away. If it doesn't, check inside the distributor cap for
evidence of spark jumping between the terminals.

You might try looking , at # 2 + 4/rest of wiring/cap, in the dark. You might see where the spark is going.

What sort of wires are you using? Solid stranded copper I hope.

I've not done the 12V /electronic thing, mine runs good with original 6V, can't help you there

(quoted from post at 09:43:15 09/27/20)
You might try looking , at # 2 + 4/rest of wiring/cap, in the dark. You might see where the spark is going.

What sort of wires are you using? Solid stranded copper I hope.

I've not done the 12V /electronic thing, mine runs good with original 6V, can't help you there

Click to expand...

Solid stranded copper I hope. " Why would you 'hope' that? Pertronix says that is a no no, but to use suppression type wires, either spiral or other.

99% of the time is a fouled plug, be it oil are fuel. Under norm firing events the spark is taking the rout of least Resistance instead of jumping the gap its following the substance that's has accumulated on the plug to ground.

A look at the working end of the plug will be help full, sometimes its a no brainier others you can tell by the darker color something has built up on it that conducts electricity counseling out the firing event..

If you get lucky just arcing as you are doing will complete the combustion event enoufh to clean the plug..

Congratulations, you have discovered the effect of a "booster gap". Google: How do booster gap plugs work, which should explain it.

I suspect the plugs are fouled with deposits - replacing the plugs should eliminate the problem. Of course the root cause is typically due to oil consumption.

You are describing fouled plugs, replace them with Autolite 437's and be on your way. A visual inspection of the plugs should confirm this before you spend the money. If you really want to be sure, switch the plug to a firing cylinder 1 or 3 .

Thank you everyone for your insights and advice. I started with looking at the spark plugs and three of four were heavy with thick wet oily crud and soot. I checked the gap on them and they were between .048 and
.055. I gapped the new Autolites to .030 and installed them.

The engine started immediately and without choke and has run really well throughout the day. I guess it has been years since I have looked at those plugs. Time just gets away sometimes.

As for the wires, I’m not sure what kind they are. They came with the Pertronix kit sold by the sponsor of this forum so I will conclude they are right.

Now I’m going to start thinking about fixing the smoking problem as well as the wiggling right front wheel.

Thanks again for all of the great replies. Jerry

(quoted from post at 07:35:52 09/27/20)

(quoted from post at 09:43:15 09/27/20)
You might try looking , at # 2 + 4/rest of wiring/cap, in the dark. You might see where the spark is going.

What sort of wires are you using? Solid stranded copper I hope.

I've not done the 12V /electronic thing, mine runs good with original 6V, can't help you there

Click to expand...

Solid stranded copper I hope. " Why would you 'hope' that? Pertronix says that is a no no, but to use suppression type wires, either spiral or other.

Click to expand...

I guess you missed the last sentence. I'm ignorant of 12V electronic conversions. But I'm learning.

I wonder if solid wires would be O.K. with resistor plugs? I hate suppression wires.